Polymerase chain reaction (PCR) is a widely used technique for the detection of pathogens. The technique uses a DNA polymerase used to amplify a piece of DNA by in vitro enzymatic replication. The PCR process generates DNA that is used as a template for replication. This results in a chain reaction that exponentially amplifies the DNA template.
Technologies for genomic detection most commonly use DNA probes to hybridize to target sequences. To achieve required sensitivity, the use of PCR to amplify target sequences has remained standard practice in many labs. While PCR has been the principle method to identify genes associated with disease states, the method has remained confined to use within a laboratory environment. Most current diagnostic applications that can be used outside of the laboratory are based on antibody recognition of protein targets and use ELISA-based technologies to signal the presence of a disease. These methods are fast and fairly robust, but they can lack the specificity associated with nucleic acid detection
Recently, it was reported that incorporating trans-1,2-diaminocyclopentane into aminoethylglycine peptide nucleic acids (aegPNAs) significantly increases binding affinity and sequence specificity to complementary DNA. See, Pokorski, et al, J. Am. Chem. Soc. 2004, 126, 15067-15073 and Myers, et al, Org. Lett. 2003, 5, 2695-2698. Despite the promise of PNAs with 1,2-diaminocyclopentane residues in the backbone, commercially viable uses of such PNAs have not been realized.
There is a need for pathogen detection methods that are highly specific and robust for use outside of a laboratory environment.